John D. Cressler, James H. Comfort, et al.
IEEE Transactions on Electron Devices
We report the first SiGe-base heterojunction bipolar transistors (HBT's). The devices were fabricated using molecular beam epitaxy (MBE), low-temperature processing, and germanium concentrations of 0, 6, and 12 percent. The transistors demonstrate current gain, and show the expected increase in collector current as a result of reduced bandgap due to Ge incorporation in the base. For a 1000-Å base device containing 12-percent Ge, a 6 times increase in collector current was measured at room temperature, while a 1000 times increase was observed at 90 K. The temperature dependence of the collector current of the Si0.88Ge0.12-base transistor is consistent with a bandgap shrinkage in the base of 59 meV. For the homojunction transistors, base widths as thin as 800 A were grown, corresponding to a neutral base width of no more than 400 Å. © 1988 IEEE.
John D. Cressler, James H. Comfort, et al.
IEEE Transactions on Electron Devices
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IEEE International SOI Conference 2010
Stefan Zollner, Craig M. Herzinger, et al.
Solid State Communications
Faraz Khan, Eduard Cartier, et al.
IEEE Electron Device Letters